Boku no Hero Academia: Ikinokore! Kesshi no Survival Kunren

 A two-part ONA taking place after season 4 (including the slice of life opening theme), class 1-A is split in two to undertake rescue training.

And as it is a good training for their provisional licences, it is taken very seriously, especially by one very unexpected student.

The story has it's fun moments, especially the Denki Kaminari moments are the star of the show, as the students split up in smaller groups to conduct a search action.  But when the area starts collapsing, they also have to find a way to save themselves and their friends from serious danger and getting injured, having to learn to build on each other.

A nice side story for sure, as it focusses on the students with not a pro-hero or villain in sight, something welcome for once as the League of Villains arc starts picking up in strenght in the main season.